Middleware does not run for static-asset requests covered by its matcher

_Found running the official Next.js e2e test suite against vinext (vinext 1.0.0-beta.8, Next.js 16.2). Error line is from the suite's own output._

**Fixture:** `test/e2e/middleware-static-files`

**Symptom:** a `.svg` under the middleware matcher is served directly and middleware never executes, so the expected response marker (`{ middleware: true }`) is absent.

**Repro:** a matcher that includes a static path; request that path and assert middleware ran.

Start with the `test/e2e/middleware-static-files` fixture and the request path used by the official Next.js e2e test suite. Reproduce a request for the matched `.svg` and trace why the static asset is served without middleware execution. Done means the response includes the expected `{ middleware: true }` marker for a static path covered by the matcher.

Written by the indexing model from the issue text.